Web�ｿｽW�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽJavaScript

getElementByID�ｿｽA�ｿｽﾏ撰ｿｽ�ｿｽAwith�ｿｽﾉゑｿｽ�ｿｽQ�ｿｽﾆ托ｿｽ�ｿｽx�ｿｽ�ｿｽr

�ｿｽy�ｿｽ[�ｿｽW�ｿｽ�ｿｽﾉゑｿｽ�ｿｽ�ｿｽdiv�ｿｽ^�ｿｽO�ｿｽ�ｿｽ�ｿｽQ�ｿｽﾆゑｿｽ�ｿｽ�ｿｽ鼾��ｿｽﾌ托ｿｽ�ｿｽx�ｿｽ�ｿｽr�ｿｽ�ｿｽ�ｿｽﾊでゑｿｽ�ｿｽBgetElementById()�ｿｽﾅ参�ｿｽﾆゑｿｽ�ｿｽ�ｿｽ鼾��ｿｽA�ｿｽ�ｿｽx�ｿｽ謫ｾ�ｿｽ�ｿｽ�ｿｽ�ｿｽID�ｿｽ�ｿｽﾏ撰ｿｽ�ｿｽﾉ難ｿｽ�ｿｽ�ｿｽﾄ参�ｿｽﾆゑｿｽ�ｿｽ�ｿｽ�ｿｽ鼾��ｿｽAwith�ｿｽ�ｿｽ�ｿｽg�ｿｽ�ｿｽ�ｿｽﾄオ�ｿｽu�ｿｽW�ｿｽF�ｿｽN�ｿｽg�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾈ暦ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ鼾��ｿｽ�ｿｽ3�ｿｽp�ｿｽ^�ｿｽ[�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽr�ｿｽ�ｿｽ�ｿｽﾄゑｿｽ�ｿｽﾜゑｿｽ�ｿｽB
�ｿｽe�ｿｽX�ｿｽg�ｿｽ}�ｿｽV�ｿｽ�ｿｽ�ｿｽ�ｿｽPower Mac G5 (2GHzx2�ｿｽA�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ4GB)�ｿｽAWindows�ｿｽ�ｿｽXP SP2 (3.0GHz�ｿｽA768MB) �ｿｽﾅ行�ｿｽ�ｿｽ�ｿｽﾄゑｿｽ�ｿｽﾜゑｿｽ�ｿｽB�ｿｽ�ｿｽ�ｿｽ�速�ｿｽx�ｿｽﾍ会ｿｽ�ｿｽx�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ[�ｿｽh�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ鼾��ｿｽﾌ値�ｿｽﾉなゑｿｽ�ｿｽﾄゑｿｽ�ｿｽﾜゑｿｽ�ｿｽB�ｿｽﾜゑｿｽ�ｿｽA�ｿｽ�ｿｽ�ｿｽ�速�ｿｽx�ｿｽﾍ環具ｿｽ�ｿｽﾉゑｿｽ�ｿｽﾙなゑｿｽﾌで、�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽﾜでゑｿｽ�ｿｽQ�ｿｽl�ｿｽ�ｿｽ�ｿｽx�ｿｽﾉゑｿｽ�ｿｽﾄゑｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽB
�ｿｽy�ｿｽT�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ1�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽs�ｿｽz
�ｿｽy�ｿｽT�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ2�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽs�ｿｽz
�ｿｽy�ｿｽT�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ3�ｿｽ�ｿｽ�ｿｽ�ｿｽ�ｿｽs�ｿｽz
OS�ｿｽu�ｿｽ�ｿｽ�ｿｽE�ｿｽUgetElementById (msec)�ｿｽﾏ撰ｿｽ (msec)with (msec)
MacOS X (10.4.7)Safari 2.0.412804201000
MacOS X (10.4.7)Firefox 1.5.0.4445030504420
MacOS X (10.4.7)Opera 9.02770501160
Windows XP SP2Internet Explorer 6440023002760
Windows XP SP2Firefox 1.5.0.4462030324100
Windows XP SP2Opera 9.068015580
�ｿｽy�ｿｽT�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ�ｿｽP�ｿｽz
�ｿｽ�ｿｽHTML�ｿｽt�ｿｽ@�ｿｽC�ｿｽ�ｿｽ
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<script type="text/javascript" src="test.js"></script>
<title>Sample</title>
</head>
<body>
<p>JavaScript Speed Test</p>
<div id="outputArea"></div>
</body>
</html>

�ｿｽ�ｿｽ�ｿｽX�ｿｽN�ｿｽ�ｿｽ�ｿｽv�ｿｽg�ｿｽt�ｿｽ@�ｿｽC�ｿｽ�ｿｽ (test.js)
window.onload = function() {
var num = 100000;
s = (new Date()).getTime();
for (var i=0; i<num; i++) {
document.getElementById("outputArea").innerHTML;
}
e = (new Date()).getTime();
alert(e-s);
}
�ｿｽy�ｿｽT�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ�ｿｽQ�ｿｽz
�ｿｽ�ｿｽHTML�ｿｽt�ｿｽ@�ｿｽC�ｿｽ�ｿｽ
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<script type="text/javascript" src="test.js"></script>
<title>Sample</title>
</head>
<body>
<p>JavaScript Speed Test</p>
<div id="outputArea"></div>
</body>
</html>

�ｿｽ�ｿｽ�ｿｽX�ｿｽN�ｿｽ�ｿｽ�ｿｽv�ｿｽg�ｿｽt�ｿｽ@�ｿｽC�ｿｽ�ｿｽ (test.js)
window.onload = function() {
var divObj = document.getElementById("outputArea");
var num = 100000;
s = (new Date()).getTime();
for (var i=0; i<num; i++) {
divObj.innerHTML;
}
e = (new Date()).getTime();
alert(e-s);
}
�ｿｽy�ｿｽT�ｿｽ�ｿｽ�ｿｽv�ｿｽ�ｿｽ�ｿｽR�ｿｽz
�ｿｽ�ｿｽHTML�ｿｽt�ｿｽ@�ｿｽC�ｿｽ�ｿｽ
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<script type="text/javascript" src="test.js"></script>
<title>Sample</title>
</head>
<body>
<p>JavaScript Speed Test</p>
<div id="outputArea"></div>
</body>
</html>

�ｿｽ�ｿｽ�ｿｽX�ｿｽN�ｿｽ�ｿｽ�ｿｽv�ｿｽg�ｿｽt�ｿｽ@�ｿｽC�ｿｽ�ｿｽ (test.js)
window.onload = function() {
var divObj = document.getElementById("outputArea");
var num = 100000;
s = (new Date()).getTime();
with(document.getElementById("outputArea")) {
for (var i=0; i<num; i++) {
innerHTML;
}
}
e = (new Date()).getTime();
alert(e-s);
}